batman-adv: Don't leak information through uninitialized packet fields

The reserved fields in batman-adv packets are not set to a constant value. The
content of these memory regions is leaked unintentionally to the network.

This regression was introduced in 3b27ffb00fbe9d9189715ea13ce8712e2f0cb0c5

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>

diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index b7c655c..9e4bb61 100644 (file)
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -214,6 +214,7 @@ static int batadv_interface_tx(struct sk_buff *skb,
 
                /* batman packet type: broadcast */
                bcast_packet->header.packet_type = BATADV_BCAST;
+               bcast_packet->reserved = 0;
 
                /* hw address of first interface is the orig mac because only
                 * this mac is known throughout the mesh

diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index 245cc9a..a438f4b 100644 (file)
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -2052,6 +2052,7 @@ static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client,
        roam_adv_packet->header.packet_type = BATADV_ROAM_ADV;
        roam_adv_packet->header.version = BATADV_COMPAT_VERSION;
        roam_adv_packet->header.ttl = BATADV_TTL;
+       roam_adv_packet->reserved = 0;
        primary_if = batadv_primary_if_get_selected(bat_priv);
        if (!primary_if)
                goto out;

diff --git a/net/batman-adv/vis.c b/net/batman-adv/vis.c
index f09cc9a..2a2ea06 100644 (file)
--- a/net/batman-adv/vis.c
+++ b/net/batman-adv/vis.c
@@ -589,6 +589,7 @@ static int batadv_generate_vis_packet(struct batadv_priv *bat_priv)
        packet->header.ttl = BATADV_TTL;
        packet->seqno = htonl(ntohl(packet->seqno) + 1);
        packet->entries = 0;
+       packet->reserved = 0;
        skb_trim(info->skb_packet, sizeof(*packet));
 
        if (packet->vis_type == BATADV_VIS_TYPE_CLIENT_UPDATE) {
@@ -890,6 +891,7 @@ int batadv_vis_init(struct batadv_priv *bat_priv)
        packet->header.packet_type = BATADV_VIS;
        packet->header.ttl = BATADV_TTL;
        packet->seqno = 0;
+       packet->reserved = 0;
        packet->entries = 0;
 
        INIT_LIST_HEAD(&bat_priv->vis_send_list);